This invention relates generally to orthotic devices and, more particularly, to a uniquely configured proprioceptive knee brace specifically adapted to support a patient's knee while providing the benefits of neuromuscular stimulation.
The human knee has an intricate anatomy and a relatively complex set of rotational movements. The primary movements of the knee comprise flexion and extension respectively defined as rearward and forward rotational movement of the tibia (knee bone), relative to the femur (thigh bone). The knee is subject to complex loads and stresses and is the joint that is most often injured during physical endeavors, including athletic or sporting activities. For example, patellar tendinitis (“jumper's knee”) is a painful condition that may result from repetitive running and/or jumping as is common when running and playing basketball, volleyball, tennis, etc.
The act of jumping and hitting the ground may overstress the patellar tendon which attaches the patella (kneecap) to the tibia, at the tibia tubercle (upper front portion) of the tibia. Patellar tendinitis is characterized by inflammation of the patellar tendon and surrounding soft tissue in an area just below the patella at the patella/patellar tendon junction. Osgood-Schlatter disease, a condition similar to patellar tendinitis, may occur in young children and adolescents and may be caused by a common phenomenon in children and adolescents wherein the bones grow at a faster rate than that of the muscles and tendons, causing tightness and pulling in the tendons and resulting in pain and inflammation.
Other conditions associated with the patella/patellar tendon junction include chondromalacia patellae, which is a condition characterized by a softening and subsequent breakdown and roughening of articular cartilage lining the patella. Ideally, the articular cartilage is smooth such that it may glide freely along the articular groove of the femur as the knee flexes or bends. Chondromalacia patellae may occur in older age groups as a result of normal wear and tear with aging. This condition may also occur in young children as a result of muscle imbalances around the knee, causing uneven wear on the lateral (outer) facet of the patella.
When chondromalacia patellae occurs in young children, it may be due to an imbalance between vastus lateralis (outer) and vastus medialis (inner) components of the quadriceps muscle, which is the large muscle on the front of the thigh. The quadriceps muscle attaches to the patella via the quadriceps tendon, which is located above the patellar tendon. In some patients, the vastus lateralis may be more powerful than the vastus medialis, resulting in a tendency for the patella to track laterally or outwardly and eventually resulting in softening and breakdown of the patella.
Still other conditions of the knee joint include meniscal (cartilage) tears, wherein shock absorption, joint stabilization, and lubrication qualities otherwise provided by the meniscal cartilage are compromised. Illio-tibial band (ITB) syndrome may occur in long distance runners as a result of running on cambered surfaces or using shoes having little cushioning. The ITB is a relatively thick strip of tendon extending downwardly from the hip joint and passing across the outside of the knee and inserting into the tibia just below the knee joint. ITB syndrome is characterized by pain in the knee joint during flexion and extension as the ITB moves backwards and forwards across the lateral side of the knee joint.
Patello-femoral pain-syndrome (PFPS), or “runner's knee”, may be defined as pain resulting from physical changes in the patellofemoral joint (the joint between the femur and the patella), which often worsens with certain activities, such as descending steps or hills. PFPS may be the result of a maltracking of the patella relative to the femur during knee flexion and extension. More specifically, PFPS may be due in part to an imbalance in the quadriceps muscles that attach to the patella. Although balance in the quadriceps muscle assists in the proper tracking of the patella, imbalance in the quadriceps muscle may cause abnormal gliding of the patella leading to eventual inflammation and pain. Similar to the above-described condition of chondromalacia patellae in young children, PFPS may also be caused by an imbalance in muscle strength between the vastus lateralis and the vastus medialis, resulting in a tendency for the patella to track laterally, causing increased stress to the knee joint.
The prior art includes many knee braces that are intended to reduce strain on injured knee components such that the knee may properly heal. Additionally, prior art knee braces may be worn as a preventative measure when the patient engages in strenuous or physically demanding activities. Unfortunately, many knee braces of the prior art suffer from several deficiencies that detract from their overall utility. For example, many of the prior art knee braces are configured to circumferentially wrap around or encircle the patient's knee so as to provide inward compressive force around the circumference of the knee joint. Such knee braces may be designed with the intention of supporting the knee joint against hyperextension, which may stretch or further damage the ligaments and tendons connected thereto. Unfortunately, such circumferential compression about the knee joint causes vascular restriction, which impedes the flow of blood to the injured area and which may extend the healing process.
For the above-described conditions of chondromalacia patellae and PFPS, wherein the vastus lateralis tends to be more powerful than the vastus medialis with resulting patellar tracking dysfunction, some prior art knee braces have been developed with the intention of correcting lateral patella tracking by providing a knee brace configuration that physically pulls or forces the patella in a medial (inward) direction. One such prior art knee brace includes a sleeve having a crescent-shaped side support adaptable to a particular shape of the patient's patella. When tractioned medially across the patella, the knee brace is understood to improve patellafemoral mechanics during knee flexion and extension.
Unfortunately, knee braces of the type described above are typically effective in providing patellar stability and reducing PFPS only when the knee brace is worn. If the knee brace is not worn, further injury to the patella may occur with corresponding pain and discomfort to the patient. Furthermore, as understood, such knee braces are adapted to generally provide treatment in healing injuries and correcting deficiencies in the knee joint using a musculoskeletal stimulation approach with little regard for neurostimulation aspects of healing. In this regard, such knee braces of the prior art, as known and understood by the present inventor, are not believed to provide the best approach to overcoming the wide array of problems associated with the knee joint.
For example, it is believed that knee braces of the prior art are inadequate in correcting patellar tracking dysfunction by merely physically pulling medially on the patella. Moreover, it is believed that knee braces of the prior art are generally ineffective in altering and correcting for muscle imbalances around the knee joint. Finally, it is believed that knee braces of the prior art fail to account for healing qualities provided through neuromuscular stimulation of numerous sensory receptors located on the patient's skin. More specifically, it is noted that one square inch of skin typically contains about 19,000 of such sensory cells, which provide information regarding at least five different senses (pain, heat, cold, touch, and pressure) to the central nervous system.
In this regard, it is believed that providing such neuromuscular stimulation to the skin surrounding the knee joint may stimulate another type of receptor called proprioceptive or stretch receptors, which are located in the muscles and tendons. Proprioceptive response relates to nerves that transmit signals to and from muscles and joints in order to control movement and function of the joints and surrounding areas. Such stretch receptors sense changes in length and tension of muscles and tendons and send information regarding such changes to the central nervous system. Proprioceptive response provides the patient with spatial orientation information regarding location and movement of joints and limbs without the patient actually seeing the limb move.
It is believed that stimulation of the proprioceptive receptors in tissue surrounding the knee joint (i.e., nerves located in the skin, bones, muscle-tendon junctions, and joints) through proprioceptive response creates chemical changes in the body which positively affects the muscles, ligaments, and tendons. More specifically, it is believed that by incorporating proprioceptive response into a knee brace, muscles and tendons surrounding the affected or injured area of the knee joint may be re-educated in proper positioning and relative movement in order to correct for abnormalities and dysfunction in the knee joint such that, over time, adverse knee conditions may be corrected.
As can be seen, there exists a need in the art for a knee brace that can alleviate symptoms of pain and discomfort associated with knee joint degeneration due to injury, wear and tear, or normal aging. Moreover, there exists a need in the art for a knee brace that provides a desired amount of focused compression on tissue surrounding the affected knee joint with minimal vascular restriction on surrounding portions of the knee joint. Additionally, there exists a need in the art for a knee brace wherein a desired amount of medial influence on the patella can be provided in order to compensate and correct for lateral patella tracking dysfunction. Furthermore, there exists a need in the art for a knee brace that combines neuromuscular stimulation with such medial influence and focused compression in order to provide the benefits of proprioceptive response in healing degeneration in the knee joint.